﻿286 Geological Society : — 



The method is one that appeals strongly to the mathematical 

 physicist. It is necessarily laborious in its present form, and 

 probably could not be worked with sufficient speed to make it a 

 practical method of forecasting ; but when forecasters have 

 acquired experience in its use, they will probably find that a 

 sufficient number of the quantities allowed for are comparatively 

 small to make it possible to expedite the calculation considerably 

 without great sacrifice of accuracy. 



The value of the work is not confined to the application to 

 forecasting, though the possibility of predicting the disturbing 

 occasions when cyclones cause merriment in the daily press by 

 moving in the wrong direction makes this the feature of most 

 general interest. Its discussion of the physical properties of the 

 atmosphere is so thorough that it constitutes a text-book of the 

 subject. Copious references to original literature are given, and 

 any meteorologist requiring serious information on any topic will 

 do well to look first in this book. The section on evaporation 

 suggests that the only limitation on the evaporation from vege- 

 tation is imposed by the difficulty of passing along the stomata 

 tubes ; this is not always true even for an isolated leaf, and is 

 certainly wrong for a carpet of grass, on account of the obstruc- 

 tion offered by the vapour from one stoma to evaporation from 

 another. The numerical data actually given, however, eliminate 

 this source of error. 



Concerning the printing and style of the book, it is only 

 necessary to say that it is published by the Cambridge University 

 Press. The index is good. H. J. 



XXIII. Proceedings of Learned Societies. 



GEOLOGICAL SOCIETY. 



[Continued from vol. xliii. p. 1138.] 



February 1st, 1922.— Mr. E. D. Oldham, F.K.S., President, 

 in the Chair. 



Mr. Cyril Edward Nowill Bromehead, B.A., F.G.S., de- 

 livered a lecture on the Influence of Geology on the 

 History of London. 



The 6-inch Geological Survey maps constructed by the Lecturer 

 were exhibited, and some of the new features pointed out. The 

 small streams now * buried ' are indicated on the maps, and the 

 historical research involved in tracing them led to an appreciation 

 of the connexion between the geology and topography on the one 

 hand, and the original settlement and gradual growth of London 

 on the other. The reasons for the first selection of the site have 

 been dealt with by several writers : below London the wide allu- 

 vial marshes formed an impassable obstacle ; traffic from the 



